Dr. Linda Buck, 2004 Nobel Laureate

Opening new doors to understanding the brain

The reawakening of a long-forgotten memory by the scent of spring lilacs in bloom or an apple pie fresh from the oven can be one of our most powerful human responses -- and one of the most mysterious.

How do we differentiate thousands of distinct odors and how do our brains perceive and remember them? Dr. Linda Buck set out to understand the sense of smell, a monumental scientific question that had long evaded explanation.

Through years of intensive research, Buck became the first to identify a family of genes that control the olfactory system, a complex network that governs our sense of smell. The genes are blueprints for a family of smell-receptor proteins in the nose that work in different combinations so that the brain can identify a nearly infinite array of odors — much like the letters of the alphabet are combined to form different words.

Buck determined that each odor-sensing cell in the nose possesses only one type of odorant receptor, and each receptor can detect a limited number of odorant substances. She then used this knowledge to determine how the identities of different odors are perceived by the brain to allow us to sense distinct odors. In later studies, she and her colleagues uncovered a sensory map in a part of the brain known as the olfactory bulb and that is virtually identical in all individuals.

Uncovering how this system works has been fundamental to understanding the machinery that controls the relay of sensory signals from the world around us to the central nervous system.

These landmark contributions to human biology open new doors to studying the brain and have numerous implications for health. They may even hold the key to understanding behaviors such as fear and aggression.

For her groundbreaking discoveries of odorant receptors and the organization of the olfactory system, Buck received the 2004 Nobel Prize in physiology or medicine.